Method for monitoring a machine tool, in particular tool breakage

摘要

The invention relates to a monitoring method for monitoring a machine tool (10), in particular tool breakage, the (i) a spindle (14), (ii) at least a first machine axis (16) and (iii) a machine control (22) which is formed for activating the spindle (14) and the machine axis (16) and for outputting machine parameters, with the automatically performed steps: (a) during the execution of a machining program for machining a workpiece (12), time-dependent detection of a spindle parameter (P) describing a power of the spindle (14), (b) detecting a signal noise parameter s describing the magnitude of a stochastic fluctuation of spindle parameter measurements (P (τ)) and / or a signal span parameter (Q) having a width of the Indicates interval (I) in which the spindle parameter measured values lie during the machining of the workpiece (12), (c) after reaching a predetermined program line of the machining continuously calculating a spindle parameter minimum value (P _{S, min} ) of the spindle parameter measured values (P (τ)) such that a current spindle parameter minimum value (P _{S, min} (τ)) is obtained; (d) continuously calculating a monitoring limit value (P) G (τ)) from the spindle parameter minimum value (P _{S, min} (τ)) and the signal noise parameter (s) and / or the signal span parameter (Q), (e) storing the current monitoring threshold (G (τ)) when the current monitoring limit (G (τ)) is less than a stored monitoring limit (G _sp ), and (f) issuing a warning message if the spindle parameter P is consistently below the stored monitoring limit (G _sp ) for a predetermined interval time (Δt).